When connecting two alternating voltage sources to each other, the matching of the sources is of interest in terms of target current control, overall efficiency and noise reduction. Such a matching is particularly relevant in a switched topology, wherein a stepped voltage waveform may be generated by a switched power inverter system and output e.g. an alternating current (AC) to e.g. the grid. The generated AC signal may hence comprise unwanted frequency components, such as e.g. harmonics, that originate from the switching process and/or the target alternating voltage waveform, and that differ from the harmonics of the required AC.
The issue of unwanted frequency components of the generated AC power has been addressed by implementing a filter blocking or suppressing certain frequencies. Inductors are e.g. known to block or reduce high-frequency components while capacitors are known to do the reverse. Components presenting less attenuation to low-frequency signals than high-frequency signals may be referred to as low-pass filters, whereas components presenting less attenuation to high-frequency signal than low-frequency signal may be referred to as high-pass filters.
Although such components may be used for reducing unwanted frequency components of the generated AC power signal, there is still a need for improved methods and devices for matching a generated alternating voltage to a desired alternating voltage waveform, and in particular in case the generated alternating voltage waveform is staircase shaped with relatively large steps in amplitude and time, i.e., wherein the difference between the target waveform and the output is not negligible.